The electrophilic aromatic substitution proceeds through a

The cyclopentadienyl anion is:

Among the following,the aromatic compounds are:
$(A)$ Heptafulvene
$(B)$ Benzene
$(C)$ Cyclopentadienyl anion
$(D)$ Cyclopentadienyl cation
Choose the correct answer from the following options:

Which of the following reactions is not an example of an addition reaction?

The correct order of reactivity towards Electrophilic Substitution Reaction $(E.S.R.)$ for the following compounds is:
$(i)$ Toluene
(ii) $m$-Methoxytoluene
(iii) Benzaldehyde
(iv) $p$-Nitrobenzaldehyde

Assertion : Nitrating mixture used for carrying out nitration of benzene consists of conc. $HNO_3 +$ conc. $H_2SO_4$.
Reason : In presence of $H_2SO_4$,$HNO_3$ acts as a base and produces $NO_2^+$ ions.